Need a Sales Leaderboard for my members - Add Ons or Plugins?

[vestaviascott]

I'm looking to facilitate a healthy competition among my forum members for most sites sold with my product.

I produce a WordPress site building system called BizLocal and my customers are using it to sell turn-key, pre-configured websites to local businesses in their area.

I'd like to give each user a means creating a monthly sales tally each time they close a sale using my software.

Are there some recommendations you have for anything that can do this? It must integrate with the Vbulletin forum software.

Ideally, it would be accessible via the users profile area and would obviously be on honor system.